CRC coding is commonly used to detect errors in data transmitted in wireless communication systems. In the evolving 3GPP LTE specification, for example, it has been proposed that 24 CRC parity bits be generated based on the entire transport block (TB). The 24 CRC parity bits are then attached to the TB, after which the TB is segmented into multiple code blocks (CBs). In the LTE proposal, 24 CRC parity bits are also calculated based on each code block (CB) and the 24 CRC parity bits are then attached to the corresponding CB. In the LTE proposal, the same generator polynomial is used in the generation of the CRC parity bits based on the transport block and in the generation of the CRC parity bits based on the code blocks. The first transport CRC encoding helps the receiving device to detect residual errors. It has been suggested that the CRC encoding of the code blocks may be used by the receiving device to reduce the number of turbo decoding processes, or to reduce the number of turbo decoding iterations, or to reduce turbo decoder memory usage. The code blocks are then channel encoded, for example, with a turbo code, prior to transmission.
The various aspects, features and advantages of the disclosure will become more fully apparent to those having ordinary skill in the art upon careful consideration of the following Detailed Description thereof with the accompanying drawings described below. The drawings may have been simplified for clarity and are not necessarily drawn to scale.